The invention relates generally to prosthetics and, more particularly, to a sensing system for placement in the digits of a prosthetic hand or arm.
The prior art contains many examples of prosthetics and, more particularly, to a sensing system for placement in the digits of a prosthetic hand or arm.
The prior art contains many examples of prosthetic sensors adapted to enable the user of the prosthesis to determine the existence of such parameters as pressure, stress or heat upon the digits of the surface of the prosthetic device. See for example U.S. Pat. No. 3,751,733 (1973) to Fletcher entitled Tactile Sensing Means for Prosthetic Limbs. Also, a generalized class of sensors for prosthetic devices exists, the purpose of which is to enable the user to gauge the movement and velocity of the prosthetic limb. In this regard, see U.S. Pat. No. 3,820,168 (1984) to Horvath, entitled System for Operating a Prosthetic limb.
None of the prior art, however, contains any method by which a user of a prosthetic device can determine or differentiate as to which of the digits (in the case of a hand) or area of a given surface of a prosthetic device is, at any particular time, subject to pressure or the like. That is, the prior art does not teach any method by which differentiation between pressure, or relative pressures, between digits or areas of a prosthetic hand or limb, can be achieved.
Further, all prior art known to the inventor pertains to the transmission of signals to the skin covering whatever organs exist at the amputation site. In distinction, the present disclosure transmits a vibrational signal to the bone stump nearest to the amputation site. From that point, neural impulses are transmitted to the posterior columns of the spinal cord and, therefrom, the brain. This represents a different neurologic circuit than is employed by the prior art known to the inventor. Accordingly, this invention reflects an effort to provide a sensor for a prosthetic device in which the wearer will not simply sense pressure, heat or movement in a generalized manner as the prior art teaches, but will be able to determine exactly which digit or which area of the prosthesis is the origin of the sensed parameter.